That, coupled with sustained drops <200 V would probably be enough for the power company to change the tap on your feeder transformer to bump the voltage up closer to nominal. But be aware that if the nature of the loading changes, you might end up with overvoltage conditions.
It's what I fear.
Honestly, if you are the only residential user at the end of a long line mostly feeding industrial farm equipment, you are going to see pretty ugly stuff.
I believe you!
Just curious: let's suppose there is some (neighbor's) heavy load on the line that is causing these fluctuations.
Would it be possible to detect the type of load (e.g. the type of heavy machinery) by plugging some measurement equipment to the mains, e.g. by measuring noise/harmonics?
I guess it would be possible, but I'm pretty confident they are all only inductive machinery (motors) without a proper power factor correction capacitor bank.
What measurement point, if not the main feed in your breaker panel (safety issues here) you could be seeing local issues, ie a half a dozen daisy chained receptacles.I've seen entire large rooms on a 20 amp breaker with 14 gauge wire all daisy chained, more than once.
Exactly: initally I thought was an issue inside my electric panel or a domestic cabling problem.
But I followed the reverse path going from the mains plugs to the breakers up to the electrical meter and ended reaching the source measuring directly on the unfused three phase supply at the cabinet,
before my electric meter (should be ~400V 11KW; I know about high safety risk this entails and I took all the precautions needed to avoid a guaranteed instant death).
I tested all three phases, the results are the same: all three have those glitches, both in respect to each other and to neutral.
The readings does not differ from any measurement taken inside the house so the issue is between the electrical company and me.
I believe that I'm at the end of a line with too small section that obey Ohm's law when one of the farmer's motor starts... I strongly believe that in NO WAY they would change the cable line section because it's a buried line and would require a huge amount of money.